1. Field of the Invention
The present invention relates to a hollow sphere from amphiphilic chitosan derivatives and a method of preparing an amphiphilic chitosan derivative complex for medical use and, more particularly, to a hollow sphere from amphiphilic chitosan derivatives and a method of preparing an amphiphilic chitosan derivative complex for medical use, which can be applied for anticancer drug delivery.
2. Description of Related Art
Currently, anticancer drug carriers have developed for anticancer chemotherapy, and liposome is considered to be an ideal drug carrier due to its unique properties to target cancer. Especially, the liposome encapsulates drugs and releases drugs at a tumor area but does not pass through normal tissue, so that the probability of destroying normal cells can be reduced. However, the liposome shows low encapsulation efficiency, high-priced processing, insufficient stability, and poor biocompatibility, so that there are still some problems in applying the liposome in the clinical treatment. Hence, there has been some research in natural polymers with good biocompatibility, in order to develop an efficient drug carrier system for anticancer chemotherapy.
Among the well-known natural polymers, chitosan is considered to be able to be applied on drug carriers, due to its low cost, high biocompatibility, and degradability. Generally, chitosan is derived from chitin by removing acetyl groups. This process, called deacetylation, release amino groups and gives the chitosan a cationic characteristic. The formula of the chitosan is represented as follows:

The chitosan has advantages of low price and good biocompatibility, and the double layer structure of the liposome is considered to be an ideal form for drug carriers. Hence, if the chitosan can be processed and form a double layer structure similar to the liposome, it is possible to apply the double layer structure made from the chitosan to the carriers for drug delivery efficiently. Presently, the double layer structure made from the chitosan is synthesized by template-coating or layer-by-layer building. However, the aforementioned methods have the disadvantages of complicated processing and high cost, so that it is difficult to be commercialized.
Therefore, it is desirable to develop a drug carrier for anticancer chemotherapy, which has a double layer structure similar to the liposome and the characteristics of the chitosan, such as low cost, high biocompatibility, and degradability.